Free Human Digestive System MCQs with Answers
188 Human Digestive System MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The human digestive system breaks food into absorbable molecules through mechanical processing, enzyme action and chemical conditions along the alimentary canal. Questions cover the mouth, stomach, small and large intestines, liver, pancreas and associated secretions, including the digestion and absorption of carbohydrates, proteins, lipids, vitamins, minerals and water.
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188 questions · page 7 of 10
- A. Mucus
- B. Sucrose
- C. Amylase
- D. Sodium bicarbonate
Explanation: The correct answer is sucrose. Human saliva contains mucus to lubricate the mouth, amylase to begin the digestion of starches, and sodium…
Correct answer: Sucrose122. The structure that does NOT contribute to the large surface area of the ileum is the presence of
- A. Villi in the inner lining
- B. Microvilli in the epithelium
- C. Muscles in the muscularis layer
- D. Circular folds in the mucosal layer
Explanation: The correct answer ismuscles in the muscularis layerThe muscularis layer's primary function is to aid in the movement of the intestines…
Correct answer: Muscles in the muscularis layer- A. Gastrin
- B. Acetylcholine
- C. Secretin
- D. Cholecystokinins
Explanation: The secretion of bile is primarily stimulated by the hormone cholecystokinin (CCK), rather than secretin.
Correct answer: Cholecystokinins- A. Serosa, longitudinal muscle, mucosa, Sub mucosa
- B. Mucosa, serosa, muscle, epithelium
- C. Serosa, Longitudinal muscles, circular muscles, sub mucosa, mucosa
- D. Serosa, Longitudinal muscles, sub mucosa, mucosa
Explanation: The correct order from outer to inner is Serosa → Longitudinal muscles → Circular muscles → Submucosa → Mucosa.
Correct answer: Serosa, Longitudinal muscles, circular muscles, sub mucosa, mucosa- A. Outer anal sphincter
- B. Both outer and inner anal sphiniters
- C. Inner and sphiniter
- D. Connot be inhibited
Explanation: The majority of protein digestion occurs in the duodenum, the first segment of the small intestine.
Correct answer: Outer anal sphincter- A. Gastrin
- B. Secretin
- C. Insulin
- D. Lipids
Explanation: Hepatic and Pancreatic secretions are also stimulated by a hormone called secretin, which is produced by the intestinal mucosa on the…
Correct answer: Secretin- A. 7.8
- B. 6
- C. 1.8
- D. 1.4
- E. 1.2
Explanation: Explanation for this question will be added soon.
Correct answer: 1.4- A. Dysentery
- B. Piles
- C. Food poisoning
- D. Peptic ulcer
- E. Dyspepsia
Explanation: Explanation for this question will be added soon.
Correct answer: Peptic ulcer- A. Monosaccharide form
- B. Oligosaccharide form
- C. Polysaccharide form
- D. All given options
Explanation: Amylase is found in saliva and breaks starch into maltose and dextrin, an oligosaccharide.
Correct answer: Oligosaccharide form- A. 3
- B. 7
- C. 8
- D. 12
- E. 13
Explanation: In the mouth, as the chewing begins, saliva is released which has the amylase enzyme. The amylase starts breaking down starch to maltose.
Correct answer: 3- A. Vitamin B12 absorption
- B. Protein digestion
- C. Carbohydrate breakdown
- D. Bowel movement
Explanation: Intrinsic factor plays a crucial role in the transportation and absorption of the vital micronutrient vitamin B12.
Correct answer: Vitamin B12 absorption- A. Sensation of taste
- B. Smell of food
- C. Presence of protein food in stomach
- D. Sight of food
Explanation: Presence of proteins in the stomach activates parietal cells to secrete gastric juice.
Correct answer: Presence of protein food in stomach- A. Glycogenolysis
- B. Gluconeogenesis
- C. Deamination
- D. Immunoglobulin synthesis
Explanation: Metabolic role of liver includes Glycogenolysis (conversion of glycogen to glucose), Gluconeogenesis(formation of glucose from…
Correct answer: Immunoglobulin synthesis- A. Lipase
- B. Trypsin
- C. Pepsin
- D. Amylase
Explanation: Pancreatic juice contains Lipase, Trypsin, and Amylase. Thus it does not contain Pepsin and Option C is the correct answer.
Correct answer: Pepsin- A. Protein digestion
- B. HCl secretion
- C. Protein absorption
- D. HCl inhibition
Explanation: Parietal cells are responsible for HCl secretion, which aids in the digestion of food, absorption of minerals, and control of harmful…
Correct answer: HCl secretion- A. Absorption of electrolytes.
- B. Absorption of water
- C. Production of vitamins
- D. Absorption of amino acids
Explanation: Absorption of nutrients occurs in the small intestine. The nutrients are absorbed through the villi of the small intestine.
Correct answer: Absorption of amino acids137. The following part Is common in both the digestive system and respiratory systems of human beings:
- A. Trachea
- B. Pharynx
- C. Larynx
- D. Oesophagus
Explanation: The pharynx is part of two body systems (the respiratory system and the digestive system) because it carries both air and food.
Correct answer: Pharynx- A. Pepsin
- B. Sucrose
- C. Enterokinase
- D. Pancreatic lipase
Explanation: The function of the pancreatic juice is to digest and break down large sugars, fats, and starches into smaller assimilable molecules.
Correct answer: Pancreatic lipase- A. Amylase
- B. Erypsin
- C. Lactase
- D. Carboxypeptidase
Explanation: Amylase is produced mostly in the pancreas, but also in the salivary glands and small intestine.
Correct answer: Amylase- A. Oxyntic cells
- B. Chief cells
- C. Mucus cells
- D. Endocrine cells
Explanation: Gastric chief cells secrete pepsin as an inactive zymogen called pepsinogen.
Correct answer: Chief cells